MOSCOW (Reuters) - Google does not change its search algorithm to re-rank individual websites, it said in a letter to Russia's communications watchdog, after Moscow expressed concerns the search engine might discriminate against Russian media.

The Roskomnadzor watchdog said earlier this month it would seek clarification from Alphabet Inc's Google over whether it intentionally placed articles from Russian news websites Sputnik and Russia Today lower in search results.

Responding to a question about Sputnik articles at a conference earlier in November, Alphabet Executive Chairman Eric Schmidt said Google was working to give less prominence to "those kinds of websites" as opposed to delisting them.

That prompted complaints from Russian authorities, with Roskomnadzor saying last week it would take action against Google if it discriminated against Russian media.

"We'd like to inform you that by speaking about ranking of web-sources, including the websites of Russia Today and Sputnik, Dr. Eric Schmidt was referring to Google's ongoing efforts to improve search quality," Google said in a letter posted on Roskomnadzor's website.

"We don't change our algorithm to re-rank," it added.

A Google spokeswoman confirmed the letter had been sent by the company but provided no further comment.

The Russian government funds Sputnik and Russia Today.

U.S. intelligence agencies have said both websites spread misinformation and published stories that were negative towards Hillary Clinton during the 2016 U.S. presidential election.